fn main() {
    let twenty = 20;                       //<1>
    let twenty_one: i32 = 21;              //<2>
    let twenty_two = 22i32;                //<3>
  
    let addition = twenty + twenty_one + twenty_two;
    println!("{} + {} + {} = {}", twenty, twenty_one, twenty_two, addition);
  
    let one_million: i64 = 1_000_000;      //<4>
    println!("{}", one_million.pow(2));    //<5>
  
    let forty_twos = [                     //<6>
      42.0,                                //<7>
      42f32,                               //<8>
      42.0_f32,                            //<9>
    ];
  
    println!("{:02}", forty_twos[0]);      //<10>
  }
